Hydrophilic end seal

ABSTRACT

A kit, apparatus, and method for sealing a junction between a manhole and a pipe within a sewer system are provided. In a first embodiment, the end of a pipe adjacent a manhole is sealed by the use of a pipe liner and a tubular sleeve made of a hydrophilic material. The tubular sleeve is held in place by a mechanical fastener and a pipe liner is installed or otherwise placed through the tubular sleeve and against the wall of the pipe. In a second embodiment, a majority of the area surrounding a junction of a pipe and a manhole is sealed by the use of a tubular sleeve made of a hydrophilic material including a flange portion, a mechanical fastener, a pipe liner, and a manhole liner.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of pending U.S. patentapplication Ser. No. 12/962,276, filed on Dec. 7, 2010.

FIELD OF THE INVENTION

The invention relates generally to an apparatus and method for repairingthe junction between a manhole and a buried pipe in fluid communicationwith the manhole, such as underground sewer pipe and the like. Moreparticularly, but not exclusively, the invention relates to a kit,apparatus, and method to seal the junction of a pipe and a manhole usingpipe liners in conjunction with a tubular sleeve made of a hydrophilicmaterial using a mechanical fastener to hold the tubular sleeve in placeduring liner installation.

BACKGROUND OF THE INVENTION

As the infrastructure of major cities and towns in the developed worldage, the sewer systems weaken. Pipe degradation, system blockage, waterinfiltration, and sewer leakage are major problems that aging sewersystems experience. As these problems persist, the sewer system mayeventually experience total failure and entire sections of the sewersystem may collapse. As a result, sinkholes may form and sewers may backup into homes and places of business. One method of addressing thiscritical infrastructure problem is the use of pipe lining techniques torehabilitate existing sewer systems.

Cured-in-place pipelining is one such technique that includesrehabilitating an existing sewer system by creating a new pipe within anexisting pipe. A liner, impregnated with a resinous material capable ofcuring and hardening, is inverted or pulled into a damaged pipe. Theliner is pressed against the wall of the existing pipe, and the resinousmaterial is allowed to cure and harden. The result is a replacement pipehaving the older pipe or “host pipe” on the exterior. The cured-in-placepipe acts to alleviate the problems caused by structural defects andblockages in the existing sewer system. Even in sewer systems where themain pipes have been rehabilitated with a cured-in-place pipe or otherpipe liners, problems still arise. Some of those problems are caused byshrinkage of the pipe liner and unsealed connections at service andmanhole junctions.

Shrinkage of a pipe liner after installation presents a problem for thelongevity and effectiveness of a sewer system. Most materials experiencesome shrinkage after installation within an existing pipe. Once the pipeliner material has been installed, an annulus between the host pipe andthe pipe liner is created due to this shrinkage of the material or dueto surface irregularities of the main pipe. The amount of shrinkage by apipe liner depends on the materials used, the thickness of the liner,the depth of the pipe, the ambient temperatures, as well as severalother factors. This shrinkage allows water and debris to enter into thesewer system from the ground surrounding the pipes, allows sewage toescape into the ground surrounding the pipes, and allows roots fromsurrounding vegetation to enter the annulus between the host pipe andthe pipe liner.

The problem of shrinkage of a cured-in-place pipe has been addressedpreviously in the art. U.S. Pat. Nos. 6,641,688 and 7,094,308 to Gerhartteach methods of sealing the annular space formed between existing sewerpipes and cured-in-place pipes. Gerhart discloses placing an unactivatedsealant at points of future liner ports and causing the sealant to beactivated to form an annulus gasket after installation of the linerthrough application of a curing means to the rehabilitative liner.Specifically, Gerhart teaches spraying an expandable material to anexisting main pipe before the application of a cured-in-place liner ator near the future liner ports. Heat is then added to the material toexpand the material while the cured-in-place liner is installed, fillingthe annular space. There are several problems with this method. First,the step of spraying the material onto the pipe may be time consumingand the sprayed-on material may fall off of the pipe or sag to thebottom of the pipe due to gravity. Secondly, there is no way ofdetermining whether the expandable material has expanded sufficientlyinto the annular space during the curing process, as the liner obstructsthe view of the annular space. Thirdly, the step of spraying thematerial onto the pipe is imprecise as there may be areas of the mainpipe that receive too much or too little expandable material resultingin an uneven wall thickness. Lastly, the sprayed-on material may bemoved by ground water leaking through cracks into the pipe. Therefore,there is a need in the art for an improved process and apparatus forsealing the annular space formed between existing sewer pipes and pipeliners.

In sewer systems where the main pipes have been rehabilitated with acured-in-place pipe, unsealed connections at service and manholejunctions create problems. An unsealed connection is generally a productof installing a pipe liner within the main pipe, then using a cuttingtool on the pipe liner at the connection to reinstate service. Currentmethods are described for example in U.S. Pat. Nos. 5,587,126;6,641,688; and 7,131,791. Once service is reinstated to the servicepipes by the use of the cutting tool, the service pipes may stillinclude leaks, cracks or other structural defects that allowinfiltration or exfiltration of fluids or sediment at or around thejunction of the main and service pipe. The service pipe and junctionwith the main pipe may be further sealed or rehabilitated by installinga second pipe liner to seal the junction. Known methods of repairing andsealing the junction of a main and service pipe where the main pipe hasbeen rehabilitated with a pipe liner include, for example U.S. Pat. Nos.5,915,419; 6,068,725; and 6,651,699. The issue of repairing a junctionof a main and service pipe has also been previously addressed in U.S.Pat. No. 6,994,118 and U.S. Pat. App. 2009/0056823, which are herebyincorporated by reference in their entireties. In these publications, aband or o-ring made of hydrophilic material is used to create a sealbetween a host pipe and a cured-in-place pipe liner at the junctionbetween a main pipe and a lateral or service pipe.

Once the main pipe and the junctions of the main and service pipes havebeen rehabilitated and sealed, the manhole and the junction of the mainpipe and the manhole (or “main pipe/manhole junction”) remain at riskfor allowing unwanted infiltration or exfiltration of fluids andsediment. Conventional manholes include a lower or bottom pan, a barrelwith a diameter no greater than the adjacent pan, a concentric oreccentric cone extending upwardly from the barrel, one or more adjustingrings to adjust the overall height of the manhole, and a casting frameon top of the adjusting rings to support a lid at an elevationsubstantially level with the surrounding pavement. Manholes may be usedfor many purposes, including acting as catch basins for storm waterdrainage, providing access to buried pipelines, junction chambers at theintersection of sewer lines, and constructing reservoirs or wetwells forpump stations. As such, the manhole structure is a critical point toseal within the sewer system because it is an area that is inundatedwith fluids and sediment. The issue of sealing a manhole utilizingcured-in-place pipelining techniques has been previously addressed inU.S. Pat. No. 7,670,086 and U.S. Pat. App. 2010/0018631, which arehereby incorporated by reference in their entireties. However, unlessthe junction between the manhole and sewer pipe is properly sealed,ground water will continue to run along the main pipe until it can enterthe sewer system where the main pipe joins the manhole.

There have also been attempts in the art to seal the junction of amanhole and a main pipe. For example, U.S. Pat. No. 5,879,501 disclosesthe use of a tubular form inserted into the main pipe at a manholejunction. The manhole is then sprayed with a cement or polymer, thetubular form is removed, and the main pipe is lined with acured-in-place pipe. This method is time consuming, requires the use ofa tubular member to act as a mold for the area around the junction, doesnot address the problem of annular space around the pipe liner, and doesnot create a fluid-tight seal around a substantial area of the mainpipe/manhole junction. With such a method, it is unclear how to fullyseal the junction of a manhole and a main pipe, as the shrinkage of thecured-in-place pipe will still allow ground water to infiltrate theannular space.

Additionally, there are deficiencies to other known methods of sealingpipe junctions when applied to the junction of a manhole and a pipe. Forexample, the use of a band or o-ring as taught by U.S. Pat. No.6,994,118 and U.S. Pat. App. 2009/0056823 would result in impreciseplacement within the host pipe, as the flexible o-ring or band may shiftwithin the pipe or fall during placement of a pipe liner. Anotherexample of material used to seal pipe junctions includes a hydrophilicrope. One sample of hydrophilic rope is a product sold under the tradename Waterstop-Rx® in the United States by the Cetco company. The use ofsuch a rope to seal the junction of a manhole and a pipe would result inimprecise placement within the host pipe, as there are no structuralelements allowing the flexible rope to remain in place. Furthermore, theuse of such a rope would not provide a complete seal, because the ropewould be unconnected at its ends, allowing water or other fluid to trackalong the edge of the rope and leak at the point where the ends abut.

Therefore, a need in the art exists for a new apparatus and method foreffectively sealing the junction between a buried pipe, such as a sewerpipe, and a manhole.

SUMMARY OF THE INVENTION

It is therefore a primary object, feature, and/or advantage of thepresent invention to provide an improved apparatus and method forrepairing the junction between a buried pipe and a manhole thatovercomes deficiencies in the prior art.

It is another object, feature, and/or advantage of the present inventionto provide a seal to both a portion of the interior of the buried pipeand the adjoining wall of the manhole.

It is another object, feature, and/or advantage of the present inventionto provide an apparatus and method for repairing the junction between apipe and a manhole which is economical to manufacture, easy to install,and durable in use.

It is another object, feature, and/or advantage of the present inventionto provide an improved method and apparatus for repairing the junctionof a pipe and a manhole that provides a compression seal to the majorityof the area at the junction.

It is another object, feature, and/or advantage of the present inventionto provide a tubular sleeve that is retained in the pipe by a mechanicalfastener, where the tubular sleeve may be installed in a pipe withminimal movement during a pipe liner installation, and where the tubularsleeve is made in a controlled setting to have a specified andconsistent wall thickness.

These and/or other objects, features, and advantages of the presentinvention will be apparent to those skilled in the art. The presentinvention is not to be limited to or by these objects, features andadvantages, and no single embodiment need exhibit every object, feature,and/or advantage.

According to one aspect of the present invention, an assembly forsealing a pipe at a manhole junction is provided. The assembly includesa tubular sleeve having an outer diameter approximately equal to a pipediameter; a mechanical fastener; a pipe liner; and optionally a manholeliner. The sleeve is constructed with a hydrophilic material and has ahardness of preferably less than 90 Shore A Durometer Scale. In oneembodiment, the hardness of the hydrophilic material may be such thatthe tubular sleeve is collapsible, but capable of being placed back intoan initial tubular conformation. The tubular sleeve may include a flangeattached to at least a portion of an end of the tubular sleeve.

According to another aspect of the present invention, a method for usingthe assembly to seal a pipe at a manhole junction is provided. Themethod includes providing the assembly for sealing a pipe having amanhole junction and placing the tubular sleeve within the pipe, where aproximal end of the tubular sleeve is aligned with the junction of thepipe and the manhole. The pipe liner is placed against the inner wall ofthe tubular sleeve. Optionally, a manhole liner is placed against thewalls of the manhole, creating a seal at the junction of the manhole andthe pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a tubular sleeve in accordance with afirst embodiment of the present invention.

FIG. 2 is a sectional view of the tubular sleeve of FIG. 1 while placedin a strained conformation.

FIG. 3A is a cross-sectional view of a pipe illustrating the tubularsleeve of FIG. 1 placed inside of a pipe, where a mechanical fastener isutilized to secure the sleeve in the pipe.

FIG. 3B is a sectional view of the tubular sleeve and mechanicalfastener of FIG. 3A within a pipe.

FIG. 4 is a sectional view of a sewer system including a manhole, mainpipe, and service pipes illustrating where the tubular sleeve of FIG. 1is placed into the main pipe.

FIG. 5 is a perspective sectional view similar to FIG. 4, showing wherea main liner is placed against the inner wall of the tubular sleeve andagainst the walls of the main pipe by the use of an inflatable bladder.

FIG. 6 is a view similar to FIG. 4 where the liner has cured.

FIG. 7 is a perspective view of a tubular sleeve in accordance with asecond embodiment of the present invention where at least a portion ofthe proximal end of the tubular sleeve includes a flange portion.

FIG. 8 is a sectional view of a sewer system including a manhole, mainpipe, and service pipes illustrating where the tubular sleeve of FIG. 6is placed into the main pipe, where a liner has been placed against thewalls of the tubular sleeve and the main pipe, and where the flangeportion of the tubular sleeve abuts the wall of the manhole.Additionally, an optional second tubular sleeve is placed between themanhole casting and the manhole liner.

FIG. 9 is a view similar to FIG. 7, showing where a manhole liner isplaced against the walls of the manhole and against the flange portionof the tubular sleeve.

FIG. 10 is a sectional view of the junction of a main pipe and a manholewhere the main liner and manhole liner have been installed inconjunction with the tubular sleeve of FIG. 6.

DETAILED DESCRIPTION OF EMBODIMENTS

The present invention relates to an apparatus and method for repairingthe junction between a manhole and a buried pipe in fluid communicationwith the manhole, such as underground sewer pipe and the like. The endof a pipe adjoining a manhole is sealed with the use of a pipe liner anda tubular sleeve made of a hydrophilic material. Alternatively, amajority of the area surrounding a junction of a pipe and a manhole issealed by the use of a flange portion attached to the tubular sleevemade of a hydrophilic material and a manhole liner.

The following definitions of terms are employed throughout thespecification and

A “pipe liner” is defined as a material that is used to provide a liningto a pipe. Pipe liners include but are not limited to cured-in-placepipe liners, folded liners, or spray-on liners.A “cured-in-place pipe liner” is a fabric capable of holding a resinousmaterial.A “folded liner” is a material constructed of a thermoplastic, such asHigh Pressure Polyethylene (“HPPE”), High Density Polyethylene (“HDPE”),Medium Density Polyethylene (“MDPE”), Polyvinyl Chloride (“PVC”), and/ormodified PVC that is used to provide a lining to pipes.A “main liner” or “main pipe liner” is defined as a pipe liner for useinside of a main sewer pipe.A “manhole liner” is defined as a material that is used to provide alining to a manhole. Manhole liners include but are not limited tocured-in-place manhole liners, spray-on manhole liners, cementitiousmanhole liners, cast-in-place manhole liners, and resin manhole liners.A “cured-in-place manhole liner” is a fabric capable of holding aresinous material.A “spray-on liner” is defined as a material that is used to provide alining to a manhole or pipe where the material is sprayed onto the wallsof the manhole or pipe.A “cementitious liner” is defined as a cement material that is used toprovide a lining to a manhole. Cementitious liners may usually besprayed, spread, or otherwise placed onto the walls of the manhole.A “resin liner” is defined as a resinous material that is used toprovide a lining to a manhole. Resin liners may be sprayed, spread, orotherwise placed onto the walls of the manhole.A “service pipe” is defined as a pipe that is lateral to a main pipe.

Referring now to the figures wherein like numerals refer to like parts,FIG. 1 is a perspective view of a tubular sleeve 10 in accordance withan embodiment of the present invention. The tubular sleeve 10 comprisesa proximal end 12, a distal end 14, a body 16 there between, and anouter wall 22 having a diameter D1. The tubular sleeve 10 is a single,unitary piece that may be made by vulcanization processes. Such methodsmay include wrapping or extruding polymeric material around a mandreland placing the loaded mandrel into a vulcanizing autoclave for apredetermined period of time. A vulcanization method is preferred forthe tubular sleeve 10, because the material may be formed in a tube ofconsiderable length to be cut into shorter tubular sleeves. Such amethod would decrease the cost of producing the tubular sleeve 10compared to other methods, allowing for the simultaneous production of aplurality of units. Other methods of forming the tubular sleeve 10include casting or molding methods, including but not limited to resincasting, injection molding, blow molding, or extrusion molding. Thetubular sleeve 10 may be produced in units of preferably 1-8 inches andmost preferred 5-7 inches in length. The tubular sleeve 10 should beless than about 10 mm in thickness, with 2-3 mm most preferred. Thetubular sleeve 10 is preferably produced in the form of a tube. However,it should also be appreciated that alternative constructions arepossible, such as where a sheet of material is formed into a tube andfused together by thermal bonding, adhesives, or other mechanicalbonding methods. It should also be noted that the tubular sleeve 10 maybe formed by taking a sheet of material and forming it into a tube byoverlapping the ends, and then securing the tubular form within the pipeby the use of mechanical fasteners. Therefore, a bonded, continuous tubeis not required to practice this invention. However, the body 16preferably comprises a generally uniform wall thickness along the lengthof the tubular sleeve.

Tubular sleeve 10 may be made of a compliant material, including but notlimited to rubber, polyurethane, or other polymers. Tubular sleeve 10 ismade of or impregnated with a material having hydrophilic properties,such that the material will swell in the presence of water. Such amaterial is preferred when the junction to be sealed experiences or isat risk of experiencing water infiltration, as the hydrophilic materialwill expand in the presence of water and extrude through voids or cracksin the passageway, thus creating a full compression seal. For examplesof hydrophilic materials for use as seals, see U.S. Pat. No. 6,328,310,6,541,106, or 6,994,118.

A feature of the tubular sleeve 10 is that the material comprising thetubular sleeve may be of such a hardness that the tubular sleeve shouldbe able to maintain its tubular shape within a conduit, such as a mainpipe. The material of the tubular sleeve of the present invention mayhave a hardness between 0 Shore A Durometer Scale and 80 Shore DDurometer Scale. It is preferred that the tubular sleeve has a hardnessof less than 90 Shore A Durometer Scale. Another feature of the sleeve10 is that outer diameter D1 is approximately equal to a diameter of aburied pipe in fluid communication with a manhole, such as undergroundsewer pipe or the like. The tubular sleeve may be retained within thepipe by utilizing a mechanical fastener before a pipe liner is placedagainst the walls of the pipe.

The tubular sleeve 10 may have the properties of an elastomericmaterial, having the ability to undergo deformation under the influenceof a force and regain its original shape once the force has beenremoved. As such, the tubular sleeve 10 may be deformed from an initialtubular conformation to a strained conformation. In the strainedconformation, the outer profile of the tubular sleeve is reduced to fitinto a pipe. As shown in FIG. 2, a force may act on the sleeve such thatthe body is folded over itself to reduce the outer diameter D1 of thesleeve. Once the tubular sleeve is placed into the pipe, the elastomericmaterial is allowed to return to its initial tubular conformation. Sincethe outer diameter D1 of the tubular sleeve 10 is approximately equal toa diameter of the pipe, the tubular sleeve will sit within the pipe. Amechanical fastener may be placed on the interior of the tubular sleeve10 to press or secure it against the interior of the pipe, to avoid theneed for an operator to hold the tubular sleeve 10 in place duringinstallation of a pipe liner.

The illustrated embodiments as described include where the buried pipeis in fluid communication with the manhole is a main pipe. However, anyother pipe in communication with the manhole, such as a lateral pipe(not shown), is within the scope of this invention. The illustratedembodiments further show where the pipe liner and manhole liner arecured-in-place liners. However, it should be understood that any othertype of pipe liner or manhole liner is within the scope of thisinvention. For example, the pipe liner may be a cured-in-place liner, afolded liner, or a spray-on liner. The manhole liner may be acured-in-place manhole liner, a spray-on manhole liner, a cementitiousmanhole liner, a cast-in-place manhole liner, and/or a resin manholeliner.

FIG. 2 is a sectional view of the tubular sleeve of the first embodimentof the present invention while placed in a strained conformation. In thestrained conformation, the sleeve 10 includes a strained portion 20along the length of the tubular sleeve that allows the outer profile ofthe tubular sleeve 10 to be reduced, allowing an easier insertion of thesleeve 10 into the pipe.

FIG. 3A is a cross-sectional view of a pipe showing the tubular sleeve10 within a pipe 32, where a mechanical fastener 18 placed against theinner wall 23 of the tubular sleeve 10 is holding the sleeve in place.The mechanical fastener 18 should be capable of radially expanding andholding the tubular sleeve 10 against the pipe 32. In one embodiment,the mechanical fastener may generally be a retaining ring. The retainingring may be a piece of flat metal formed into a generally circular shapehaving its ends held together with a pin. An operator may place thetubular sleeve 10 within the pipe 32, place the mechanical fastener 18within the tubular sleeve 10, and remove the pin. Removal of the pinwill allow the mechanical fastener 18 to radially expand against theinner wall of the tubular sleeve 10, pressing the outer wall of thetubular sleeve against the inner wall of the pipe 32. As such, theretaining ring may have an expanded or final diameter similar to thehost pipe. Alternatively, such a retaining may be constructed of a shapememory alloy or metal and fabricated to have an initial diameter roughlyequivalent to the pipe diameter. The shape memory allow may be deformedunder pressure to fit a smaller diameter, placed within the tubularsleeve, and allowed to return to its initial pre-stressed conformation,holding the tubular sleeve in place against the pipe. Any othermechanical fastener capable of holding the tubular sleeve 10 in place iscontemplated for use with this invention. For example, a ratchetingring, a hose clamp, a hydraulic ring, or any other retaining ring thatkeeps the tubular sleeve 10 in an open state within the pipe 32 may beutilized. Other mechanical fasteners that may be used include screws,nails, or anchors. It should be noted that the mechanical fastenerscontemplated for use with this invention should be constructed of arust-resistant material or a material that has been treated with arust/oxidation inhibitor. It should also be noted that if the mechanicalfastener or retaining ring includes a portion that protrudes into thepipe (such as a worm gear or screw), the area of protrusion should beoriented so that pipe flow is not obstructed (as shown in FIG. 3A). Suchan orientation may generally be described as near the top of the pipeinterior.

FIG. 3B is a sectional view of the tubular sleeve 10 and mechanicalfastener 18 of FIG. 3A within a pipe 32. FIG. 3B shows the use of acircular, cylinder shaped mechanical fastener 18 placed near an end ofthe tubular sleeve 10. While the length of the mechanical fastener isshown to be substantially less than the length of the tubular sleeve 10,it should be appreciated that the length of the fastener 18 could be thesame or even longer than the length of the sleeve 10. In addition, itshould be noted that when using a fastener such as shown in FIG. 3B, itshould be of minimal thickness to avoid creating blockage. The thicknessof the mechanical fastener 18 in this and all the figures is exaggeratedto show placement and structure of the component. In FIG. 3B, the thinmechanical fastener 18 is placed near the proximal end 12 of the tubularsleeve 10. In this embodiment, the mechanical fastener 18 is placed atthe proximal end 12 because the pipe liner to be installed within thepipe will invert through the pipe through the proximal end 12 of thetubular sleeve 10 toward the distal end 14. Therefore, a major role ofthe mechanical fastener 18 is to ensure that the pipe liner easilyaligns with and travels through the tubular sleeve 10 duringinstallation. If the mechanical fastener 18 is not used, the tubularsleeve may sag or move within the pipe during a pipe liner installation,resulting in misplacement of the tubular sleeve within the pipe. Assuch, it may be said that the mechanical fastener is placed near theleading end of the tubular sleeve 10. The leading end of the tubularsleeve is generally the end that first receives the pipe liner. However,as mentioned above, it is contemplated that the mechanical fastener 18be the same length or longer than the length of the tubular sleeve 10.In these circumstances, the location of the mechanical fastener 18 doesnot matter. It is also contemplate that two mechanical fasteners 18 beutilized, with one at the proximal end 12 and the other at the distalend 14 of the tubular sleeve 10.

FIG. 4 is a sectional view of a sewer system including a manhole 30,main pipe 32, service pipes 34, a main pipe/manhole junction 36, and amain/service junction 38. FIG. 4 illustrates where the tubular sleeve 10is deformed into the strained conformation as depicted in FIG. 2, andplaced into the main pipe 32 such that the proximal end 12 of thetubular sleeve 10 is adjacent the main pipe/manhole junction 36.Additionally, mechanical fastener 18 is shown near distal end 14 oftubular sleeve 10. After the tubular sleeve 10 is placed into the mainpipe 32, the tubular sleeve 10 is allowed to expand back into itsinitial tubular conformation. The elasticity of the sleeve 10 will causethe sleeve to revert from the strained conformation to the initialtubular conformation to fit the sleeve 10 against the wall of the mainpipe 32. The tubular sleeve 10 may be secured against the wall of themain pipe 32 using the mechanical fastener 18. In certain embodiments,the sleeve 10 comprises a thin material (<10 mm) and has an outerdiameter D1 substantially identical to the diameter of the main pipe. Assuch, the tubular sleeve 10 allows for a liner to line the main pipe 32without creating significant gaps or protrusions in the main pipe.

FIG. 5 is a view similar to FIG. 4 showing a main liner 40 placedagainst the inner wall of the tubular sleeve 10 and against the walls ofthe main pipe 32 using mechanical fastener 18. After the tubular sleeve10 is placed into the main pipe 32, a cured-in-place main liner 40,impregnated with a resinous material capable of curing and hardening, isinserted through the tubular sleeve 10 and against the sleeve and thewalls of the main pipe 32. As shown in FIG. 5, the main liner 40 ispressed against the wall of the main pipe 32 and the inner wall of thetubular sleeve 10 by the use of an inflatable bladder 42. There areseveral methods that may be employed to use the inflatable bladder 42.The inflatable bladder 42 may be inverted into the main pipe 32 afterthe main liner 40 is already within the main pipe 32; the inflatablebladder 42 may be inverted into the main pipe 32 along with the mainliner 40; or the inflatable bladder 42 may be may be pulled into placeby an operator and subsequently inflated by air or another fluid.Alternatively, the main liner 40 may have a fluid-impermeable coating onone side, allowing the main liner 40 to inflate without the use of abladder.

FIG. 6 is a view similar to FIG. 5, showing the pipe system after themain liner 40 has cured. After the main liner 40 is pressed against thewalls of the main pipe 32, the resinous material is allowed to cure andharden, holding the tubular sleeve 10 in place between the main liner 40and the main pipe 32. Even if the end of the main liner near the manholewere to shrink, the tubular sleeve 10 acts to fill the annular spacebetween the main liner 40 and the main pipe 32. Since features ofembodiment include using a hydrophilic material for the tubular sleeve,the hydrophilic material of the tubular sleeve 10 will expand in thepresence of water and/or extrude through voids or cracks in the mainpipe 32, thus creating a full compression seal in the annular spacebetween the main liner 40 and the main pipe/manhole junction 36.

In operation, the tubular sleeve 10 works as follows. An assembly isprovided, comprising a tubular sleeve 10 having a proximal end 12 and anouter diameter D1 approximately equal to a main pipe diameter; amechanical fastener 18; and a main liner 40 impregnated with a resinousmaterial capable of curing and hardening. The tubular sleeve 10 isconstructed of a hydrophilic elastomeric material having a hardnessbetween 0 Shore A Durometer Scale and 80 Shore D Durometer Scale.However, it is preferred that the tubular sleeve has a hardness of lessthan 90 Shore A Durometer scale. The tubular sleeve is placed into astrained, possibly non-tubular conformation so that the outer profile ofthe sleeve is reduced to fit inside of a main pipe. The sleeve is placedinto a main pipe such that the proximal end 12 of the sleeve 10 isadjacent a junction 32 of a manhole 30 and a main pipe 32. Once placedwithin the main pipe, the sleeve is allowed to expand back into itsinitial tubular conformation. The tubular sleeve may have a relativelytight fit within the pipe, as the outer diameter of the tubular sleeveshould have an outer profile that matches the inner profile of the pipeonce placed against the pipe wall. An operator then secures the tubularsleeve 10 against the wall of the main pipe 32 using the mechanicalfastener 18. The main liner 40 is then inserted into the main pipe andthrough at least a portion of the tubular sleeve. The main liner ispressed against the inner wall of the tubular sleeve, and the resinousmaterial is allowed to cure and harden. In situations where the mainliner has cured against the wall of the main pipe, the main liner may becut with a saw or the like at the junctions with service pipes in orderto reinstate service to the main pipe.

Usually within about 48 hours after curing the main liner, a manholeliner 150 (see FIGS. 9 and 10) impregnated with a resinous materialcapable of curing and hardening may be placed into the manhole adjacentthe main pipe. The manhole liner is pressed against the walls of themanhole and the resinous material is allowed to cure and harden. Thecured manhole liner is cut with a saw or the like around the junctionswith other pipes, such as main pipes, to reinstate service to themanhole. Alternatively, other manhole liners may be utilized as statedabove. After installation of the tubular sleeve, the main liner, andoptionally the manhole liner, water will enter the annular space betweenthe liners and the main pipe and/or manhole. Since the tubular sleeve isconstructed of a hydrophilic material, the material will expand and/orswell upon contact with water, making a compression seal and extrudingthrough voids or cracks in the main pipe and/or manhole.

Once this process is complete, there may still be infiltration of waterand sediment between the manhole liner and the walls of the manhole,entering from the top of the manhole where the lid sits (or manhole“casting”). Therefore, the assembly may further include a second tubularsleeve 160 (see FIGS. 8-10) having an outer diameter approximately equalto a manhole casting 131 diameter. In such a case, the second tubularsleeve 160 is placed into the manhole casting 131 before placement ofthe manhole liner 150. The second tubular sleeve 160 is placed withinthe manhole casting. A second mechanical fastener or retaining ring 162may be placed on the inner wall of the second tubular sleeve 160 tosecure it to the manhole casting 131. The manhole liner is placedagainst an inner wall of the tubular sleeve. The resinous material inthe manhole liner is allowed to cure and harden, and any infiltrationfrom the manhole casting is then staunched by the tubular sleeve placedbetween the manhole liner and manhole casting.

In such a system, an advantage of using a second tubular sleeve made ofhydrophilic material at the manhole casting is that the tubular sleevewill provide a cushion to the cured manhole liner for freeze-thawcycles, as the manhole casting is susceptible to expansion andcontraction due to the elements. The primary advantage of using a secondtubular sleeve is that most points of water and sedimentinfiltration/exfiltration are sealed using the hydrophilic material.However, another point of water and sediment infiltration/exfiltrationwithin the sewer system is the junctions of main and service pipes. Assuch, the assembly may further include a service liner to seal theservice pipes. The use of a second tubular sleeve for the manholecasting and a service liner is optionally considered for use with allembodiments of the present invention.

FIG. 7 is a perspective view of a tubular sleeve 110 in accordance withan additional embodiment of the present invention. Tubular sleeve 110comprises a proximal end 112, a distal end 114, a body 116 therebetween, an outer wall 122 having a diameter D2, and a flange portion118. As in the tubular sleeve 10 of FIGS. 1-6, the tubular sleeve 110 isa single, unitary piece that is made by a vulcanization, casting, ormolding method, including but not limited to resin casting, injectionmolding, blow molding, or extrusion molding. The tubular sleeve 110 maybe molded directly into the form of a tube with a flange portion.However, alternative constructions are possible where the tube may beformed by taking a sheet of material and forming it into a tube, thenfusing the material into a tube and attaching a flange portion bythermal bonding, adhesives, or other mechanical bonding methods. Thebody 116 and flange portion 118 comprise a generally uniform wallthickness along their respective lengths. The outer diameter D2 of thetubular sleeve 110 is approximately equal to a diameter of a pipe forwhich the tubular sleeve 110 is to be inserted.

In the tubular sleeve 110 shown in FIG. 7, the flange portion 118surrounds the entire periphery of the proximal end 112 of the tubularsleeve 110. However, alternative constructions are possible, as theflange portion 118 may extend around a portion of the tubular sleeve110. The flange portion 118 acts to provide a seal to the majority ofthe area of a main pipe/manhole junction, providing a seal to theportion of the manhole adjacent the main pipe. The amount of flangeportion 118 present on the tubular sleeve will depend on theconstruction of the junction of the manhole and main pipe. For instance,some main pipes are situated above the floor of the manhole, which iscalled a drop inlet. A drop inlet is depicted in FIGS. 7-10. Other mainpipes are situated at the floor of the manhole, and a bench is addedonto the manhole floor making a trench, allowing the contents of themain pipe to pass through the manhole in the area between the bench. Forinstances where the manhole utilizes a bench in the manhole floor, theflange portion 118 should surround the periphery of the tubular sleeve118 such that the flange portion contacts the wall of the manholeadjacent the main pipe. It is possible to construct a tubular sleeve 110such that a portion of the periphery of the distal end 112 includes aflange portion 118 by molding the tubular sleeve 110 as such. It ispreferred to produce a tubular sleeve 110 where the flange portion 118extends around the entire periphery of the proximal end 112, so that aninstaller may simply cut away a section of flange portion 118 with aknife, saw, or the like to tailor the tubular sleeve 110 to a specificmain pipe/manhole junction.

FIG. 8 is a perspective sectional view of a sewer system including amanhole 130, main pipe 132, and service pipe 134 illustrating where thetubular sleeve 110 is placed into the main pipe 132. FIG. 8 also showsthat a main liner 140 has been cured against the wall of the tubularsleeve 110 and the main pipe 132, and that the flange portion 118 of thetubular sleeve 110 abuts the wall of the manhole 130. As discussed abovein regards to FIGS. 1-6, the tubular sleeve 110 may be placed into astrained conformation and placed into the main pipe 132 such that theproximal end 112 of the tubular sleeve 110 is adjacent the mainpipe/manhole junction 136. After the tubular sleeve 110 is placed intothe main pipe 132, the tubular sleeve 110 is allowed to expand to itsinitial tubular conformation. A mechanical fastener or retaining ringmay be placed on the inner wall of the tubular sleeve 110 to secure itto the main pipe 132 such as described above regarding FIGS. 3-6. Then amain liner 140, impregnated with a resinous material capable of curingand hardening, is inserted into the main pipe 132 and pressed againstthe walls of the tubular sleeve 110. The main liner 140 is thencured-in-place with or without the use of an inflatable bladder.

FIG. 9 is a view similar to FIG. 8, showing a manhole liner 150impregnated with a resinous material capable of curing and hardeninginserted into the manhole 130 and pressed against the wall of themanhole 130 as well as against the flange portion 118 of the tubularsleeve 110. Once the main liner 140 has been installed, it isadvantageous to install a manhole liner 150 usually within 48 hours ofplacing the main liner 140 into the main pipe. The time frame to installthe manhole liner 150 is noted because the hydrophilic material used forthe tubular sleeve 110 will begin to swell at some point after placementwithin the main pipe 132. It is preferred to install the main liner 140and manhole liner 150 over the tubular sleeve before it has begun toswell, which is usually within 48 hours. However, longer time periodsare within the scope of this invention, depending on the hydrophilicityof the material used for tubular sleeve 110. The liners provide counterpressure to the tubular sleeve 110, allowing the material of the sleeveto provide a compression seal to the main pipe 132 and walls of themanhole 130.

The manhole liner 150 of FIG. 9 is shown pressed against the wall of themanhole 130 by an inflatable manhole bladder 152. The manhole bladder152 is inflated by inflation device 154, and the resinous material isallowed to cure and harden. The inflation device 154 and inflatablemanhole bladder 152 are removed from the manhole, and service to thepipes in the manhole 130 is reinstated by the use of a saw or othercutting tool.

FIG. 10 is a sectional view of the main pipe/manhole junction 136 wherethe main liner 140 and manhole liner 150 have been installed inconjunction with the tubular sleeve 110. The figure shows that themanhole liner 150 comes into contact with the main liner 140 at the mainpipe/manhole junction 136, with the body 116 of the tubular sleeve 110against the wall of the main pipe 132 and the flange portion 118 againstthe wall of the manhole 130.

In operation, the tubular sleeve 110 is used as follows. An assembly isprovided. The assembly comprises a tubular sleeve having a flangeportion, a proximal end, a distal end, a body between the ends, and anouter diameter approximately equal to a main pipe diameter; and a mainliner impregnated with a resinous material capable of curing andhardening. The tubular sleeve is constructed of a hydrophilic materialhaving a hardness between 0 Shore A Durometer Scale and 80 Shore DDurometer Scale. However, it is preferred that the tubular sleeve has ahardness of less than 90 Shore A Durometer Scale. The distal end of thetubular sleeve is deformed to a strained, non-tubular conformation sothat the outer profile of the body of the sleeve is reduced to fitinside the main pipe. The tubular sleeve is placed into a main pipe suchthat the proximal end of the tubular sleeve is adjacent a junction of amanhole and a main pipe and the flange portion abuts the wall of themanhole. Once placed within the main pipe, the body of the elastictubular sleeve is allowed to revert and expand to its initial tubularconformation. The tubular sleeve may then be secured to the pipe using amechanical fastener on the inner wall or an adhesive on the outer wallof the tubular sleeve. The tubular sleeve should have a relatively tightfit within the pipe. The main liner is then placed into the main pipethrough the tubular sleeve. The main liner is pressed against the innerwall of the tubular sleeve, and the resinous material is allowed to cureand harden. In situations where the main liner has cured against thewalls of the main pipe to cover openings of service pipes, the mainliner may be cut with a saw or the like at the junctions with servicepipes in order to reinstate service to the main pipe.

Within 48 hours after curing the main liner, a manhole liner impregnatedwith a resinous material capable of curing and hardening is placed intothe manhole adjacent the main pipe. The manhole liner is pressed againstthe wall of the manhole and the flange portion of the tubular sleeve,and the resinous material is allowed to cure and harden. The curedmanhole liner is cut with a saw or the like around the junctions withother pipes to reinstate service to the manhole. After installation ofthe tubular sleeve, main liner, and manhole liner, water will enter theannular space between the liners, the main pipe, and the manhole. Sincethe tubular sleeve is constructed of a hydrophilic material, thematerial will expand and/or swell upon contact with water, extrudingthrough voids or cracks in the main pipe and manhole to seal thejunction between a manhole and a main pipe.

Another embodiment of the invention (not shown) provides a tubularsleeve with a relatively low hardness. In this embodiment, the hardnessof the material comprising the tubular sleeve is less than 90 Shore ADurometer Scale. This allows the material to act as an adjunct to themain liner during installation. As such, the tubular sleeve may beconstructed to be much longer than the first two embodiments, as it maybe designed to run the length of the main liner, up to 500 feet inlength. This embodiment may therefore be used to seal two mainpipe/manhole junctions, as it may run from a first manhole to a secondmanhole within the sewer system. The outer diameter of this embodimentof the tubular sleeve may be considerably less that the diameter of themain pipe, as the softer material will stretch when used with a mainliner. Other than those stated differences, the tubular sleeve should beotherwise similar to the previous embodiments, utilizing a similarthickness, material, and construction method.

In the third embodiment, a tubular sleeve having a proximal end and ahardness less than 90 Shore A Durometer Scale rests within a pipe suchthat an end of the sleeve is adjacent a junction of the manhole and thepipe. An operator, machine, or robot places a pipe liner within thetubular sleeve. The pipe liner is preferably a cured-in-place liner, butother pipe liners are considered for use as well. The pipe liner isinflated or otherwise pushed or expanded toward the wall of the pipe,forcing the tubular sleeve toward the wall of the pipe. If acured-in-place pipe liner is used, a resinous material impregnated inthe pipe liner is then allowed to cure and harden. The installed pipeliner and tubular sleeve may then be cut with a saw or the like aroundthe junctions with service pipes to reinstate service to the pipe. As inthe previous embodiments, a manhole liner may be placed into the manholeadjacent the main pipe and altered to reinstate service.

An optional feature of the embodiments of the present invention includesadding an adhesive to the outer wall of the tubular sleeve. The adhesivemay cover at least a portion of the outer wall, to assist in holding thetubular sleeve within the main pipe. Types of adhesives for use with thepresent invention include but are not limited to pressure-sensitiveadhesives, double-sided tapes, or adhesive foams. It is preferred toinclude a paper or polymeric backing onto the adhesive, so that aninstaller may quickly peel the backing, insert the tubular sleeve intothe pipe, and press the adhesive against the pipe or casting. It shouldalso be noted that the tubular sleeve may be secured to the mainpipe/manhole junction by including the adhesive on the flange portion ofthe tubular sleeve that abuts the wall of the manhole.

The present invention has many attendant advantages. First, the presentinvention provides a solution to the problem of shrinkage ofcured-in-place pipe liners or other pipe liners creating annular spacebetween the liner and the host pipe. Secondly, the present inventionprovides a method that ensures the area surrounding a junction is sealedevenly with a material that provides a compression seal between the pipeliner and the pipe and/or manhole. Thirdly, the present inventionprovides a method and apparatus that provides a fast and neatinstallation of a member to seal annular space, without the need forspraying or pasting methods to attach the material to the host pipe.

It should be understood that various changes and modifications to thepresently preferred embodiment described herein will be apparent tothose skilled in the art. Such changes and modifications may be madewithout departing from the spirit and scope of the present invention andwithout diminishing its attendant advantages. It is, therefore, intendedthat such changes and modifications be covered by the appended claims.

1: An assembly for sealing a junction of a manhole and a pipecomprising: a first tubular sleeve having a proximal end, a distal end,a tubular body, and an outer diameter approximately equal to the pipediameter, the tubular sleeve comprising a hydrophilic material; a pipeliner positioned within the first tubular sleeve and extending generallygreater than the tubular body; and a mechanical fastener adapted toretain the shape of the first tubular sleeve independently of the pipeliner or a bladder. 2: The assembly of claim 1, wherein the firsttubular sleeve has a hardness less than 90 Shore A Durometer Scale. 3:The assembly of claim 2, wherein the outer diameter of the tubularsleeve is approximately equal to the pipe diameter after installationwithin the pipe. 4: The assembly of claim 3, wherein the pipe liner is acured-in-place pipe liner. 5: The assembly of claim 1, wherein themechanical fastener is a retaining ring. 6: The assembly of claim 1,wherein the first tubular sleeve further comprises a flange portionattached to at least a portion of the proximal end of the first tubularsleeve. 7: The assembly of claim 6, wherein the first tubular sleevecomprises an elastomer. 8: The assembly of claim 1, further comprising amanhole liner positioned adjacent to the first tubular sleeve. 9: Theassembly of claim 8, wherein the manhole liner is selected from thegroup consisting of cured-in-place manhole liners, spray-on manholeliners, cementitious manhole liners, cast-in-place manhole liners, andresin manhole liners. 10: The assembly of claim 9, wherein the pipeliner is a cured-in-place liner and the manhole liner is acured-in-place manhole liner. 11: The assembly of claim 1, wherein thepipe liner is selected from the group consisting of a cured-in-placepipe liner, a folded liner, or a spray-on liner. 12: The assembly ofclaim 1, further comprising: a second tubular sleeve having a diameterapproximately equal to a diameter of a casting of the manhole, thesecond tubular sleeve comprising a hydrophilic material. 13: Theassembly of claim 12, further comprising an adhesive on an outer wall ofthe first and second tubular sleeves. 14: The assembly of claim 1,wherein the first tubular sleeve has a length between 2 and 10 inches.15: The assembly of claim 14, wherein the first tubular sleeve has athickness of less than 10 mm. 16: The assembly of claim 15, wherein thefirst tubular sleeve has a thickness of 1-4 mm and a length of 2-8inches. 17: A method of sealing a junction of a pipe and a manholewithin a sewer comprising: providing a tubular sleeve constructed of ahydrophilic material having a proximal end, a distal end, an inner wall,and an outer wall having a diameter approximately equal to the pipediameter; providing a pipe liner impregnated with a resinous materialcapable of curing and hardening; positioning the tubular sleeve into thepipe such that the proximal end is adjacent the manhole; securing thetubular sleeve within the pipe using a mechanical fastener adapted toretain the shape of the tubular sleeve independently of the pipe lineror a bladder against the inner wall of the tubular sleeve; inserting thepipe liner through at least a portion of the tubular sleeve; andpositioning the pipe liner against the tubular sleeve and pipe. 18: Themethod of claim 17, further comprising: deforming the tubular sleeveinto a strained configuration prior to positioning the tubular sleevewithin the pipe. 19: The method of claim 17, further comprising:providing a manhole liner; and placing the manhole liner against a wallof the manhole. 20: The method of claim 19, wherein the tubular sleevehas a flange portion attached to at least a portion of the proximal endof the tubular sleeve; wherein the tubular sleeve has a hardness lessthan 90 Shore A Durometer Scale; and wherein the manhole liner is placedagainst the flange portion of the tubular sleeve. 21: The method ofclaim 20, wherein the mechanical fastener is a retaining ring. 22: Themethod of claim 21, wherein the pipe liner is a cured-in-place liner;wherein the manhole liner is a cured-in-place liner; and wherein thepipe is a main pipe. 23: The method of claim 17, wherein the tubularsleeve is secured to the pipe by placing the mechanical fastener againstthe inner wall of the tubular sleeve and radially expanding themechanical fastener, pressing the tubular sleeve against the pipe. 24:The method of claim 23, wherein the tubular sleeve has a hardness ofless than 90 Shore A Durometer Scale. 25: A method of sealing a sewersystem having a pipe and a manhole in fluid communication, comprising:providing a first tubular sleeve constructed of a hydrophilic materialhaving a proximal end, a distal end, an outer wall having an outerdiameter approximately equal to the pipe diameter, and a hardness lessthan 90 Shore A Durometer Scale; positioning the first tubular sleeveinto the pipe such that the proximal end is adjacent the manhole;securing the first tubular sleeve against pipe with a first mechanicalfastener; providing a pipe liner; inserting the pipe liner through atleast a portion of the pipe and the tubular sleeve and/or firstmechanical fastener; pressing the pipe liner against at least a portionof the tubular sleeve and/or first mechanical fastener; providing asecond tubular sleeve constructed of a hydrophilic material having anouter wall having a diameter approximately equal to a diameter of acasting of a manhole, and a hardness of less than 90 Shore A DurometerScale; providing a manhole liner; positioning and securing the secondtubular sleeve against the casting of the manhole; and positioning themanhole liner against the second tubular sleeve and a wall of themanhole. 26: The method of claim 25, wherein the pipe is a main pipe.27: The method of claim 25, wherein the pipe is a lateral pipe. 28: Themethod of claim 25, wherein the liner is impregnated with a resinousmaterial capable of curing and hardening prior to positioning the liner.29: The method of claim 25, further comprising: providing an adhesive tothe outer wall of the second tubular sleeve; and pressing the adhesiveagainst the casting of the manhole. 30: The method of claim 25, furthercomprising: providing a second mechanical fastener to an inner wall ofthe second tubular sleeve; and securing the second tubular sleeveagainst the casting of the manhole using the second mechanical fastener;wherein the first tubular sleeve and the second tubular sleeve aresecured by radially expanding the first mechanical fastener and thesecond mechanical fastener. 31: The method of claim 25, wherein thefirst tubular sleeve has a flange portion attached to at least a portionof the proximal end of the first tubular sleeve; and wherein the manholeliner is placed against the flange portion of the first tubular sleeve.32: A kit for sealing a junction of a manhole and a pipe in fluidcommunication comprising: a first tubular sleeve having a proximal end,a distal end, an outer wall, and an outer diameter approximately equalto the pipe diameter, the tubular sleeve comprising a hydrophilicmaterial; a pipe liner; and a first mechanical fastener adapted toretain the shape of the first tubular sleeve independently of the pipeliner or a bladder. 33: The kit of claim 32, wherein the first tubularsleeve has a hardness of less than 90 Shore A Durometer Scale. 34: Thekit of claim 33, wherein the first tubular sleeve further comprises aflange portion attached to at least a portion of the proximal end of thefirst tubular sleeve. 35: The kit of claim 34, wherein the first tubularsleeve comprises an elastomer. 36: The kit of claim 34, furthercomprising an adhesive on the flange portion of the first tubularsleeve. 37: The kit of claim 32, further comprising a manhole liner. 38:The kit of claim 37, wherein the pipe liner is selected from the groupconsisting of a cured-in-place liner, a folded liner, and a spray-onliner; and wherein the manhole liner is selected from the groupconsisting of a cured-in-place manhole liner, a spray-on manhole liner,a cementitious manhole liner, a cast-in-place manhole liner, and a resinmanhole liner. 39: The kit of claim 32, further comprising a secondtubular sleeve constructed of a hydrophilic material having an outer wanhaving a diameter approximately equal to a diameter of a casting of themanhole. 40: The kit of claim 39, further comprising a second mechanicalfastener having a diameter approximately equal to a diameter of thecasting of the manhole. 41: The kit of claim 32, further comprising anadhesive on an outer wall of the first tubular sleeve. 42: The assemblyof claim 5, wherein the retaining ring is adapted to form a completering about an interior of the first tubular sleeve. 43: The method ofclaim 21, wherein the retaining ring is adapted to form a complete ringabout an interior of the tubular sleeve.